Sunday, January 8, 2017

A Theory on The Disappearance of Atlantic Salmon in CT

Now, I do not claim to be as knowledgeable as basically any fisheries biologist, but being that I have spent a lot of time looking into the subject and a pretty substantial amount of time fishing and observing the Connecticut River watershed I think I have at least a reasonable understanding of the fishery. I have also learned, through the work of others, about similar cases involving both salmon and other anadromous salmonids. Take this for what it is, an angler's view of the decline of one of the greatest sport fish to swim in CT waters.

People are without a doubt the most destructive and dangerous animal to ever live on God's Green Earth. And there may be no period of time when humans had less concern for the Earth then the industrial revolution. In CT nearly every body of water large enough was dammed, cutting off valuable spawning ground in nearly every river salmon ran up. The last naturally spawning salmon recorded in CT waters occurred during the Civil War.

To the common fishhead, the dams may seem to be he main culprit. On closer examination that is clearly not the case. Initially, when the salmon restoration began, there were some substantial returns to the rivers. But as time progressed fewer and fewer salmon came back despite many juveniles being stocked. Even in a year with terrible flows and temperature, like 2015 and '16, substantial numbers of salmon parr prevailed. I have fished the Salmon river in September before the fall trout stocking and caught as many as 50 salmon parr in a less than a half mile of river. And in the spring I catch numerous silver smolts in all parts of the watershed. What then happens to these smolts? I suspect a similar situation is now being played out in the Maritimes, where striped bass not traditionally found that far North are being blamed for the consumption of outgoing smolts. Mind you, I'm not suggesting that striped bass were not common in the Connecticut River when salmon runs were more sustainable. There were certainly more of them "back in the day". The variable that has changed here is the available forage. Herring and shad, which were historically frequent in the same region, are depleted so dramatically that they have ceased to provide the striped bass with the food they look for during their spring migration. Despite the dramatically low herring returns, striped bass still stack up at the mouths of rivers in he spring, at the same time that thousands of bite sized salmon smolts are migrating out. Just as the loss of eel grass has left sea run brook trout at the mercy of striped bass and bluefish, the lack of large quantities of fat-rich herring has left salmon smolts at the mercy of the same predators.

It is no secret that man of the fish swimming in the Connecticut River watershed are far from their native range. Smallmouh and largemouth bass, as well as brown and rainbow trout, eat numerous juvenile salmon each year. I have caught four large smallmouth in the Salmon River that either had a live salmon parr in their throat or coughed up dead ones. After the spring stocking of juveniles I catch stocked trout, fish that would not often naturally reach their size in such small streams, that have bellies full of fry and parr. If there is any issue that is directly related to the rivers themselves, this is it. In Alaska this issue has been identified by fisheries biologists. Invasive pike are directly effecting the salmon returns.

As far as what happens once the smolt get out of the river, I don't know. I could speculate on it all day, but the ocean is a place I have not studied near as much as the rivers that I live very close to. But what I do know is that most biologists think the biggest cause for low salmon returns throughout the North Atlantic is not in the rivers themselves but in the oceans, and that these causes are nearl impossible to reverse. And I know that with the current situation there is not much hope for the future of Atlantic salmon in CT, or anywhere else in the US for that matter. It is truly a tragedy that this may well end up being the last, or one of the last true adult anadromous salmon caught by an angler in the Salmon River:



8 comments:

  1. Intriguing thoughts RM. It's certainly something to bring up to a coldwater fisheries biologist to see if there has been any work done in the same direction of thought. If not, perhaps it would help create another avenue for the biologists to consider.

    Do you know what the thermal range is for salmon Parr? Like you, I have a few streams near home which have runs of salmon. In my case, they are landlocks, and the young are wild fish. But it's amazing to me, how you can go down to these streams to try and catch trout up to about early July when things start to warm, and then you can catch small bass and a host of other sunfish species or fall fish. Amazingly, the "coldwater" fish that you literally cant avoid all summer - salmon parr. The darn stream could be 73 degrees, and you cant "not" catch parr. Its always amazed me.

    It makes me wonder if Parr are more heat tolerant than adult or even grilse aged fish... come to think of it, perhaps that's why adult brookies suffer greater losses in years like this past one than young, small fish...

    Any way, thanks for making me think!
    Be well
    Will

    ReplyDelete
    Replies
    1. Unfortunately the only issue here that we can attempt to solve right now is the herring runs, and as we know very little about what is happening to them that is a tricky problem that a lot of great minds are trying to figure out . Smallmouth and trout are both popular gamefish and the only way to solve that would be to stop stocking and institute some sort of kill on site policy for browns, rainbows, and bass... which would be wildly unpopular.

      I am not sure what the optimal range is for salmon parr but I have seen them feeding and thriving when water temps were very near 80 degrees.

      Delete
  2. The CT River Valley middens, or native american dumps, have been noted to be full of shad bones and absent of salmon bones from what I've read, casting doubt that there ever really was a substantial salmon run, or run at all, in the CT River. I'm no archeologist, just someone who's read up on the topic for whatever that's worth...

    ReplyDelete
    Replies
    1. There definitely was a run of salmon in the Connecticut, as Atlantic salmon were found here well before there was any sort of stocking. In all likelihood it was always a comparatively small run as this is right at the southern end of their native range, but clearly there was a run. It may be the case that the native peoples fished primarily for shad being that they were always more prevalent and are a much easier fish to catch with net or spear.

      Delete
  3. Good theory, up north in Canada the stripers are making a return to the coast of New Brunswick (northern) and Nova Scotia affecting the salmon rivers. Some anglers are concerned and some older say they (stripers)are returning as they used to be there. Loss of habitat, ell grass, and reduced prey makes salmon parr and smolt easy targets. Good question for the experts.

    ReplyDelete
    Replies
    1. Thank you, from what I've heard stripers were making it farther North than they ever had been before.

      Delete
  4. Interesting write up. However, there is no question that a stocked salmon population will never have the same run as a wild population. The two can't be compared. This is evident not only in the Northeast e.g Merrimack River but also out west. California has been trying to revive a steelhead run in Russian river for almost twenty years only for efforts to be in vain. In my opinion there are always many contributing factors but always two seem to be present; overfishing and dams. "Show me a river with a dam and I'll show you a river without a salmon run.

    Ps
    Great blog by the way. Love following it, keeps me going through the winter 😉

    ReplyDelete
    Replies
    1. True, stocked salmon parr don't have the perfectly adapted genetics that wild salmon do. But that does not account for the rapid decrease in runs after a few years of what initially seemed to indicate success in getting renewed salmon runs. And though I agree completely that dams spell disaster, the dam on the salmon river should not effect salmon returns there. Not only is the fishway very passable, but in moderate to high water even the face of the dam itself can be passed. If the dams were stopping incoming adults Steve Gephard would be seeing them stacked up bellow the dam when he dives there, and if it was stopping outgoing smolts they would stack up above the dam or just stay in the river and become land locked, neither of which is occurring based on my frequent observations in that location.

      Delete